The long-term goal of this program is to reduce the risk of pesticide-related neurological disease in humans by better understanding environmental exposure pathways. The broad program objectives are to: 1. Investigate and correlate the incidence and prevalence of neurological diseases and pesticide usage to identify and understand the risk factors that may have an inference of association with neurological diseases. 2. Investigate the potential neurological effects of pesticides and pesticide by-products and their transport mechanisms. 3. Develop methods for public outreach and education to reduce risk to human health based on knowledge of exposure pathways and potential neurological affects. The experimental focus for this proposal is to determine which pesticides cause neurological changes. The specific aims below are designed to provide an initial risk factor assessment, based on the correlation of neurological incidence data and pesticide usage data, and an initial characterization of the effect that specific pesticide chemicals have on the nervous system: 1. Perform an epidemiological study of neurological disease incidence and pesticide use in North Dakota. 2. Define the extent to which commonly used pesticides induce neurotoxicological impairment. 3. Initiate the development of laboratory methods to fractionate and assess pesticide chemical class and breakdown products from air particulates and evaluate potential effects using the in vitro studies in Aim 2. 4. Compile information on current pesticide education and protection programs and develop methods to facilitate transfer of research findings to potentially at-risk populations. A substantial body of evidence exists indicating that pesticide exposure is associated with a number of health problems, including neurologic dysfunction. This study will add to the scientific knowledge base of neurotoxic effects in humans from exposure to pesticides and is a step toward achieving the goal of the prevention of pesticide-induced neurodegenerative disease through a better understanding of their effects and human exposure.